Fiocchi Hull Failure
 

Has anyone else experienced this? This is a Fiocchi 28ga hull, or, what's left of one. This has happened once before, and I can't point to anything unusual in the hull, or crimp, prior to shooting.
I shot 125 rounds today, and all were loaded, on a MEC 9000, at the same time. All the crimps were satisfactory, and all the hulls had been reloaded, twice. They began as NPEs. What seems to have happened is the hull was weaker than the crimp, and the forward half of the hull, wad, and 3/4 oz load went downrange as a single 'slug'. What's even more remarkable, was the target broke. Not dust, but many pieces.
The remnant of the hull popped right out, and I immediately checked the bore to see if the remainder of the hull was inside, which it wasn't. Just another thing to make me go 'huh?'.

This used to happen to me with Federal Gold Metal shells if I reloaded them too many times. The center of the hull gets thinner with each firing until it can't resist separating at its weakest point. Never shot Fiocci hulls but their wall thickness just can't handle the many reloads. Give your once fired hulls a squeeze in the middle and compare to your many times fired hulls and see if there is a noticeable difference. Both Federal and Fiocci are straight walled hulls.

I've had it happen with Fiocchi and Estates, which are Federals, both in 28ga. Never saw the portion of the hull leave the muzzle. You would think you'd see something that big going down range.

What kind of powder?

Universal has been said to burn kinda hot, certainly I notice more wrinkling and melting in the hull which would result in either erosion as state above or embrittlement after a few reloads.

20/28, which I have always believed to be (thermally) hotter than others.

The old peters blue magic shells would do it all the time after loading a couple of times

I have experienced Fiocchi shells with a thinness to them in spots if you give them a light squeeze. If I find that its thin I just toss it. Its definitely after reloading them a few times. I'm happy with 1 or 2 then done with these.